There is an ongoing need for blood clotting substrates having improved blood clotting activity. Such structures can be suited to use in various applications, such as medical applications, surgical applications and the like, or wherever and whenever reduction of blood clotting time is desired.
Many blood clotting substrates are currently commercially available. Hemostatic bandages incorporating fibrinogen and/or thrombin, both natural products, are available. However, these naturally-derived products can be expensive to obtain and prepare for use in hemostatic substrates, since they require isolation from their source materials, formation into suitable substrate forms and subsequent sterilization. Likewise, hemostatic bandages exist which incorporate various additives, such as zeolite crystals or chitosan, as hemostasis enhancers. Again, preparation of these substrates can be expensive due to the complicated processes necessary to stably incorporate these solid powder materials into the substrate.
U.S. Pat. No. 8,133,484 discloses an adhesive material comprising gelatin and a non-toxic cross-linking material such as transglutaminase. The adhesive material is useful for medical purposes as hemostatic products. The hemostatic products are useful for the treatment of wounded tissue. The background section of this patent provides a detailed history of hemostatic devices.
It would be desirable to develop a blood clotting substrate having a comparatively simple design which could be made from relatively inexpensive synthetic materials, and has adequate surface characteristics to enhance blood clotting without incorporation of extraneous materials.
U.S. Pat. No. 7,745,223 discloses a method to increase the adhesion strength of coagulated blood on a surface by increasing the surface interaction of blood-inherent components like fibrin/fibrinogen and thrombocytes by treating the surface by exposing it to ionized atoms or molecules. The surface treatment according to the invention is applied on plastic disposables used in blood diagnostics (e.g. hemostasis analysis) as well as medical implants like artery sealings. The improved blood clot adhesion results in higher diagnostic security due to reduced measurement failure (e.g., for patients with increased thrombocyte content) and in better significance of special tests (e.g., hyperfibrinolysis diagnosis).
U.S. Pat. Nos. 5,344,611 and 5,455,009 describe processes for reducing hemostasis time in blood collection devices by plasma-treating an inside wall surface of a polymeric blood collection tube, or by inserting a plasma-treated plastic insert into such a collection tube. However, U.S. Pat. No. 5,344,611 discloses that not all plasma-treated plastics demonstrate improved clotting times.
The present inventors have discovered an integrally formed substrate, made from a single synthetic polymer, which acts to enhance blood clotting, without incorporation of dissimilar powders or foams.